Circuit breaker



Aug. 25, 1931. w. M. AUSTIN ET AL 7 1,820,687

CIRCUIT BREAKER Original Filed Feb. 4, 1921 Mm B I ATTORNEY Patented Aug. 25, 1931 UNITED STATES PATENT OFFICE WALTER M. AUSTIN AND JOHN B. MACNEILL, OF WILKINSBURG, PENNSYLVANIA, A-

SIGNORS TO WESTINGHOUSE ELECTRIC 85 MANUFACTURING COMPANY, A CORPOBA- 'IION F FENNSYLVAN IA CIRCUIT BREAKER Ap lication filed February 4, 1921, Serial No. 442,382.

an efficient form of locking mechanism which is not subject to accidental disengagement and which, at the same time, may be easily operated.

The invention is primarily designed to be employed in connection with circuit breakers that are subject to shocks, such as gun shocks, where the circuit breakers are used in connection with battleships or in forts.

The mechanism consists of a trigger lever and a locking lever for the trigger disposed side by side and pivoted at opposite ends. The locking lever is provided with a lug that normally lies in the path of a lug on the trigger lever, and the locking lever must first be moved to permit passage of the lug on the trigger lever. At a farther point in the travel of the locking lever, it engages the trigger lever to move the trigger out of locking engagement with the circuit-breaker handle. A compression spring inserted between an extension of the trigger lever, beyond the pivoted end thereof, and the free end of the locking lever serves to normally maintain the two levers in locked position. As shown in the accompanying drawings: Figure 1 is a side elevational view of a circuit breaker having our improved form of latching device applied thereto, and

Figs. 2 and 3 are detail views of the main latching members.

The circuit breaker is mounted on a usual panel 4 and comprises a pair of stationary contact members 5, a main bridging member 6 and arcing tips 7 and 8. A handle lever 9 controls the movement of the bridging member 6 and is provided with an extension 10 in which a roller 11 is supported on a pin 11a in position to be engaged by a trigger lever 12 when the handle is in its lowermost, or closed, position.

lVhen the handle is moved about a pivot 13 to its uppermost position, it releases the bridging member 6 and permits such member to be moved to open position by a spring Renewed November 3, 1928.

14 that is fastened, at its lower end, to the frame 15 of the circuit breaker.

The trigger lever 12 is pivoted to the frame 15 at 16 and has an extension 17 that serves as a seat for a spring 13. ger lever 12 is provided also with a pair of lugs 19 and 20 which co-operate with lugs 21 and 22, respectively, on a locking lever The locking lever 23 is pivoted at to the frame 15 and is provided witha seat 25 and an extension 26. The locking lever 23 may be actuated either manually by a handle 27 or by an automatic tripping mechanism 28 that operates a plunger 29 to trip the lever 23.

The lug 21 normally lies in the path of the lug 19 and prevents u )ward movement of the trigger lever 12 about its pivot 16. When the locking lever 23 is moved upwardly, however, the lug 21 passes out of the path of the lug 19 and the lug engages the lug 20 and raises the trigger lever 12, thus releasing the roller 11 of the handle lever 9 and permitting the spring 1 1.- to more the bridging member 6 to open position.

As the spring 18 serves to normally main tain the levers 12 and 23 in locked position, the extension 26 is provided so that, when the handle is returned to closed position, the roller 11 will engage the extension 26 to depress the outer end of the lever 23 and thus cause both it and the lever 12 to move to open positions and permit the entrance of the roller 11 into latched en gagement with the trigger 12 after which the lugs 21 and 22 move into the path of the lugs 19 and 20 and lock the trigger.

It will be seen that shocks to the circuit breaker cannot cause the trigger 12 to accidentally release the handle 9 because the trigger 12 is locked in closed position by the lever 23, and a shock from such direction as would tend to cause disengagement of the trigger lever 12 will have the oppo site effect on the locking lever 23, while a shock from an opposite direction that tends to move the locking lever to released position would act to more firmly maintain the trigger lever 12 in locked position.

.It will also be apparent that the lock- The triging mechanism Will operate effectively at any angle in which the apparatus may be placed, and that it may be readily employed in various other types of construction.

We claim as our invention I 1. A locking device comprising, in combination, a trigger lever pivoted adjacent to one end, a locking lever disposed alongside of the trigger lever in substantial par allelism thereto and pivoted adjacent to its end Which is farthest removed from the pivoted end of the trigger lever, an extension on the trigger lever at a point beyond its pivot, a spring interposed between said extension and the free end of the locking lever, a hooked portion formed on the free end of the trigger lever and adapted to engage a third lever, a lug on the locking lever normally lying in the path of a lug on the trigger lever to prevent movement of the trigger lever about its pivot, and an extension beyond the pivoted end of the locking lever in position to be engaged by the said third lever to cause rotative movement of the locking lever and permit the said third lever to be moved into locking engagement with the trigger lever.

2. Means for positively latching a circuit interrupter in closed position, and mechanical means releasable only When said latching means is to be unlatched for positively locking the said latching means in its latching position only after the circuit interrupter has been closed and positively latched.

3. Means for positively latching a circuit interrupter in closed position, a projection on said latching means and mechanical means releasable only When said latching means is to be unlatched and having a positive locking engagement with said projection only When said circuit interrupter has been positively latched in closed position.

4. A circuit interrupter including a movable current-carrying member and an operating mechanism therefor, an extension on said operating mechanism, a latch for engaging and positively restraining said extension after said operating mechanism has moved the current-carrying member to closed position and a mechanical locking device that automatically engages and positively locks the latch after said latch has positively restrained said extension, and leaves said latch unlocked during the closing movement of said extension, and means responsive to each release of said locking device to release said latch.

5. Latching means for retaining a circuit interrupted 1n closed-c1rcuit position, means for locking the latching means and means.

for engaging and releasing said latching means after each release of said locking means, means for maintaining said locking means in its unlocked position When said latching means. is in its unlatched position.

uary, 1921.

\VALTER M. AUSTIN. JOHN B. MACNEILL. 

